Graceful shutdown in Kubernetes is not always trivial

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Leveraging Kubernetes in your CI/CD processes, you can’t just stop your application: firstly, it should stop receiving new requests and — which is even more significant — to complete the existing ones.

By implementing this strategy, you can avoid any downtime during the deployment process. However, even using very popular technologies (such as NGINX and PHP-FPM), you still can encounter challenges that will lead to a surge of errors with each deployment. To illustrate it, I’ll start with a brief theory.

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